[Lldb-commits] [PATCH] D69148: Disable exit-on-SIGPIPE in lldb

Sat Oct 19 00:02:13 PDT 2019

labath added a comment.

In D69148#1714785 <https://reviews.llvm.org/D69148#1714785>, @vsk wrote:

> The death tests are flaky. I've noticed two issues:
>
> 1. When run under lit, the DisableExitOnSIGPIPE doesn't actually exit when it receives SIGPIPE. Dtrace suggests that the unit test process inherits an "ignore" sigaction from its parent.
> 2. When run in parallel, exiting causes the unit test to run atexit destructors for other unit tests lumped into the SupportTests binary. One of these is a condition_variable destructor and it hangs. Also, gtest warns: `Death tests use fork(), which is unsafe particularly in a threaded context. For this test, Google Test detected 21 threads.`
>
>   So I plan to give up on testing "EnableExitOnSIGPIPE" and will write a non-death test to get some coverage.

gtest gives you a (somewhat rudimentary) mechanism of ensuring death tests run in a single threaded fashion. It consists of tacking "DeathTest" at the end of your test case name (like `TEST(SignalDeathTest, Whatever)`). These kinds of tests are run first, hopefully before the tests which spin up various other threads.

As for the parent "ignore" action (it's more likely to be a signal mask, actually), this can be reset with an appropriate sigprocmask(2) call.

================
Comment at: lldb/tools/driver/Driver.cpp:850
 #if !defined(_MSC_VER)
   signal(SIGPIPE, SIG_IGN);
   signal(SIGWINCH, sigwinch_handler);
----------------
I don't think this line does anything anymore.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D69148/new/

https://reviews.llvm.org/D69148